float --> PLFLT.   This change also had the beneficial side effect of getting rid of compilation warnings.
float --> PLFLT.   This change also had the beneficial side effect of getting
rid of compilation warnings.

svn path=/trunk/; revision=2741

FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot,FreeScienceCommunity/PLPlot